Horan added, "They've given me a camera for the movie, so we're going to be going around [filming]."

"We've always had a camera with us," Horan said. "Like when we were touring America in the summer, we had like a camera with us every day and we were just kind of documenting stuff. 'Cause if it ever did come to a movie, then we'd have stuff ready for it."

The untitled concert flick will be directed by Super Size Me's Morgan Spurlock and is set to hit theaters in August of next year.

"Morgan works well because...he did a lot of documentary movies," Horan said. "That's more so what we want our movie to be. It's going to be a concert movie, but with a documentary side than concert side so we wanted to get our personalities across because the fans know us, but we want them to know us deeper."

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